Gun barrel



May 10, 1960 J. WILSON 2,935,913

GUN BARREL Filed April 24, 1956 FIG. 2

INVENTOR John L. Wilson BY W 6M1, MMBM ATTORNEYS diameter of the chamber portion of the liner.

,holdsthe liner in place and prevents movement.

edsaws Pa GUN BARREL John Wilson, Madison, Conn.,-assignor to Olin Mathieson' Chemical Corporation, New Haven, Court, a corp'oration of Virginia Application April 24, 1956, Serial No. 580,198

2 Claims. (CI. 89-16) This invention relates to gun barrels, and has for its object the provision of improvements in gun barrels of the type having a barrel liner reinforced with a surrounding layer of glass fibers impregnated with a plastic binding material. The improved barrel of the invention comprises a metal chamber sleeve having a threaded end for connection to a gun receiver, and means for securely fastening the barrel liner to the chamber sleeve. The barrel liner with the chamber sleeve attached is covered with a composite layer formed of glass fibers impregnated with a resin binder.

The preferred barrel of the invention comprises a barrel 'liner formed of various metals having relatively thin walls insuflicient to contain the explosive force, including an enlarged chamber portion for receiving a shot shell or cartridge. The chamber is larger in diameter than the bore and where the twoparts join there is a rapid change in diameter-forming a sloping shoulder just ahead of the chamber. Also, the chamber end of the liner is slightly, larger than finished dimension. The

. chamber sleeve has a neck portion shaped to make a tight fit with the shoulder and the chamber sleeve has an inside diameter just slightly larger than the outside In other words, the inside dimensions of the chamber sleeve are just slightly less than the chamber dimensions plus the wall thickness of the liner. The liner is preferably press vfitted into the chamber sleeve until the shoulder of the liner is in contact with the converging neck portion of the chamber sleeve. Inasmuch as the liner is made oversize, the residual stress from the press fitting effectively The sleeve can be heat treated to any desired property prior to assembly which does not change the character of the metal. The tensile strength of the liner which results from cold working of the metal is not lost and there is no ridging of the chamber as in the case of sleeves soldered tobarrel liners.

The invention will be better understood after considering the following discussion taken in conjunction with the accompanying drawings, in which,

Fig. 1 is a perspective view of a barrel liner and chamber sleeve of the invention in position for assembly, and

Fig. 2 is a perspective view, with parts in section, of a gun barrel'in an embodiment of the invention.

The barrel of the invention illustrated in the drawings comprises a barrel liner 1 in the form of a tube of any suitable metal which may be formed as by drawing, machining or electroforming, and may have a wall thickness as required. it may be made of a tough and corrosion resistant alloy steel, or of aluminum or an aluminum alloy when lightness is desired, or of electroformed nickel, chromium, iron or-alloys when highly polished surfaces and corrosion resistance are desired. For convenience in illustrating the invention, I have selected a shot gun barrel, it being understood that the invention is also applicable to rifle barrels. The liner comprises 2,935,913 Patented May 10,

a barrel portion 2 having an interior bore proportioned to meet the requirements of the particular gun, and a chamber portion 3 proportioned to meet the requirements of the particular shot shell. internally the barrel liner is similar to a conventional shot gun barrel, and the tapered throat 4 of the chamber results in a tapered outside shoulder 5. The barrel liner can be given any'suitable heat treatment or mechanical working prior to forming the barrel.

The chamber sleeve 6 has a neck portion 7 similar in shape internally to the tapered shoulder 5, and a chamber portion 8. The inside dimensions of the neck portion 7 and chamber portion 8 are just slightly smaller than the corresponding parts of the exterior of the chamber and shoulder of the liner and the two parts are pressfitted together. Because of the tight fit and the engagement of the shoulder with the neck, the barrel liner cannot be displaced in a forward direction or rotated by firing and there is no force resulting from the use of a gun that can displace the liner rearward. The chamber sleeve has a threaded end 9 which is screwed into the receiver of the gun (not shown) in the usual way.. While the sleeve illustrated has threads for connection to the. receiver, it is to be understood that any other suitable connecting means may be used such ascross pins. The sleeve is preferably formed of any suitable steel and is given any desired heat treatment prior to connection with the barrel liner.

The surrounding reinforcing layer 12 of glass fibers 13 and resin binder 14 can be formed in various-ways. For example, the glass fibers illustrated are in the form of thread consisting of glass filaments, such as the product known as Fiberglas, wound tightly and in overlapping layers over the barrel liner. This helically wound fiber layer is impregnated wih a resin such as a thermoplastic or thermosetting resin that is hard and strong when set.

The glass fibers may also be in the form of tape or cloth wrapped around the barrel, or in the form of staple fibers applied in a slurry or liquid resin-forming material. The resin binder may be an epoxide or epoxy resin, 21 tetrafluoroethylene polymer known as Teflon, or a phenolformaldehyde or resorcinol-formaldehyde adhesive of the type that are liquid when applied and set on heating, or set spontaneously, to a hard infusible and insoluble resin.

The exterior of the reinforcing layer may be covered with a separate layer of resin coating, or with a sleeve or jacket of metal such as a tube of aluminum 15.

As is apparent in Fig. 2 of the drawings, the wall 7 thickness of the tube 1 is necessarily of uniform thickof a relatively thin-walled metallic tube covered with a I jacket of glass reinforced resin, said tube being fabricated of a metallic material having physical and heat treat properties of a given character, one end of said tube being formed with a sloping shoulder terminating in a chamber: the improvement which embraces a device for connecting the barrel to a receiver comprising a metal sleeve adapted to receive the chamber end of the barrel, said sleeve engaging said tube in a pressed fit and being fabricated of a metallic material having physical and heat treat 7 properties of a different character from those of said tube one end of the sleeve being formed with threads adapted to mate with corresponding threads formed in said receiver whereby the barrel is connected to the receiver.'

3 2. A firearm barrel as recited in claim 1 wherein the chamber portion of the tube represents a larger diameter than the diameter of the main body of the tube and the sleeve is formed with a neck portion corresponding to the sloping shoulder of the tube, the shoulder and neck being eifective to engage one another whenever the sleeve is threadedly connected with said receiver, said sleeve having a wall thickness greater than the wall thickness of the tube whereby the sleeve can be threaded with greater ease and with coarser threads than the tube.

UNITED STATES PATENTS Benson Feb. 6, Maxim Jan. 10, Warner May 2, Hogg July 22, Collins M July 30, Clarkson et a1 Feb. 28, Ramberg May 1, Sullivan Feb. 5, Day Aug. 5-,

FOREIGN PATENTS Great Britain Dec. 7, 

1. IN A FIREARM BARREL OF THE TYPE FORMED COMPOSITELY OF A RELATIVELY THIN-WALLED METALLIC TUBE COVERED WITH A JACKET OF GLASS REINFORCED RESIN, SAID TUBE BEING FABRICATED OF A METALLIC MATERIAL HAVING PHYSICAL AND HEAT TREAT PROPERTIES OF A GIVEN CHARACTER, ONE END OF SAID TUBE BEING FORMED WITH A SLOPING SHOULDER TERMINATING IN A CHAMBER: THE IMPROVEMENT WHICH EMBRACES A DEVICE FOR CONNECTING THE BARREL TO A RECEIVER COMPRISING A METAL SLEEVE ADAPTED TO RECEIVE THE CHAMBER END OF THE BARREL, SAID SLEEVE ENGAGING SAID TUBE IN A PRESSED FIT AND BEING FABRI- 